Yesterday (today if you're in the US), Sun released the latest version of its virtualisation solution, VirtualBox 3.1. Among speed improvements and other smaller features, the biggest news is that Virtualox 3.1 introduces something called teleportation: you can move running VMs between machines - servers or clients, different architectures, different host operating systems, it doesn't matter to VirtualBox. Coincidentally, this reminded me of an idea I once had about moving running applications between machines.

Yes-- It's very nice right-clicking a node in my ESX cluster, selecting "Enter Maintenance Mode", and watching all my running VM's move to other nodes. Watching them move around in response to load is also nice.

Xen has also had this functionality for awhile, so I'm glad to see VirtualBox catching up.

I'm curious to see how "cross platform" it is-- Under VMWare ESX, it's annoying enough to move between two similar CPU's with slightly different feature sets. If the running VM can't tell that it's 64-bit CPU just changed to a 32-bit CPU, then I would think that the VM isn't capable of exploiting very much of the higher-end CPU's.